This invention relates to restrictors in general and is particularly directed to a reciprocating restrictor for use in a fluid pressure system in which the restrictor is operated automatically by fluid pressure in the system.
Conventional restrictors for fluid pressure systems comprise a wire located in an orifice to reduce the size of the orifice and thereby regulate fluid flow through the orifice. It is common practice to selectively reciprocate the wire within the orifice to keep the orifice free from contaminants while maintaining a predetermined flow of fluid through the orifice. This eliminates the need for filters and screens to prevent contaminants from plugging the orifice in such systems.
Automatic reciprocating movement of the wire in such systems has been accomplished by attaching the wire to a piston which, under changing fluid pressures, imparts an automatic reciprocating movement to the wire. In these arrangements, the piston is spring loaded in one direction and pressure operated in the opposite direction. Pressure is used to move the piston and fixed wire against the biasing force of the spring.
While these devices operate satisfactorily in some fluid systems, they are complex, requiring a plurality of parts and much more space than presently available in other fluid systems.